@Falcon Webmention sending tests using webmention.rocks URLs (all 21 of them in a single post)
https://webmention.rocks/test/1
https://webmention.rocks/test/2
https://webmention.rocks/test/3
https://webmention.rocks/test/4
https://webmention.rocks/test/5
https://webmention.rocks/test/6
https://webmention.rocks/test/7
https://webmention.rocks/test/8
https://webmention.rocks/test/9
https://webmention.rocks/test/10
https://webmention.rocks/test/11
https://webmention.rocks/test/12
https://webmention.rocks/test/13
https://webmention.rocks/test/14
https://webmention.rocks/test/15
https://webmention.rocks/test/16
https://webmention.rocks/test/17
https://webmention.rocks/test/18
https://webmention.rocks/test/19
https://webmention.rocks/test/20
https://webmention.rocks/test/21